1. Field of the Invention
The present invention relates to bending devices for pipes, tubes, and conduits. More particularly, the present invention relates to devices to assist in using hand benders. Still more particularly, the present invention relates to a stand for increasing the use capability and portability of hand benders.
2. Description of the Prior Art
Benders are used to form straight runs of conduit (or pipe or tube) at particular angles in order to conform to surface structures to which they are coupled. Conduit benders are particularly useful in the electrical trades for establishing runs through which wiring is passed without kinking, getting snagged, or generally having an unsightly appearance when the conduit is applied to exterior walls.
For the most part, there are three types of benders used by those in the trades. The first is a hand bender and the second is an automated machine bender. The hand bender is relatively inexpensive in comparison to the machine bender. It includes a handle section and a head or shoe. The head includes an curved conduit capturing recess. A straight piece of conduit is inserted into the recess and the user restrains one end of the conduit while rotating the handle to cause the conduit to curve in conformance with the arc of the recess. The hand bender is limited in that it can only produce one bend angle, the most common being a 90xc2x0 bend. Unfortunately, the user may wish to bend the conduit at other angles and so is required to purchase benders having differing recess curves.
Further, hand benders are limited in that they can only be used to create, at least easily, a single bend in the conduit. There are, however, times when a conduit run must have multiple bends in order to conform to surfaces having multiple protrusions. However, hand benders cannot be used to establish multiple bends in a single run without going through significant contortions. This can be a time consuming and frustrating process that may require experimentation and unacceptable conduit shape. All of this can lead to increased cost for a particular project, even when using a low-cost hand bender.
The automated machine bender is a viable alternative to the hand bender and is particularly suited to formation of conduits with multiple angles. Further, it is likely to reduce the time required to form conduit with multiple bends. Nevertheless, the cost of automated benders is seen to be cost prohibitive for many tradespeople. In addition, for the individual tradesperson, an automated bender is generally not sufficiently portable to enable a single person to maneuver it from one job site to another. Unfortunately, they appear to be too large to conveniently stow away in a secured location on a job site (such as a lockbox), but not so big that they cannot be pilfered. In addition, they require access to electricity in order to operate. When at a site remote from conventional electrical outlets, a generator is required.
The third type of bender is a mechanical bender. The mechanical benders presently available are bulky, hard to operate, and difficult to transport easily. For that reason, they tend to be permanent-type fixtures not generally suited for the individual having his or her own bending equipment to be moved from one job to another.
An example of an automated bender is described in U.S. Pat. No. 4,546,632 issued to Van Den Kieboom et al. The Van Den Kieboom automated bender includes a rolling cart and requires an electrical power supply to operate. There are often situations where the user may not have easy access to an electrical supply, thereby making such a bender ineffective at remote or non-supplied sites. Further, such relatively complex systems are prone to failures that may require periodic expected and unexpected costly maintenance, driving the real price of the device much higher than the original purchase price. U.S. Pat. No. 3,949,584 issued to Pearson et al. describes a similar type of automated bender and therefore has similar limitations associated generally with such automated systems.
Therefore, what is needed is a device to enable bending of conduit, pipe, or tube at selectable angles. Further, what is needed is such an assistive conduit bending device that enables the formation of multiple bends of a conduit. Yet further, what is needed is an assistive conduit bending device that is relatively transportable by a single individual and that can be secured with convenient job site storage means. What is also needed is such an assistive device that is not as complex, power-supply dependent or costly as existing automated benders.
It is an object of the present invention to provide an assistive device to enable hand bending of conduit, pipe, or tube at selectable angles. It is also an object of the present invention to provide an assistive conduit-bending device that enables the formation of multiple bends of a conduit. Further, it is an object of the present invention to provide an assistive conduit bending device that is relatively transportable by a single individual and that can be secured with convenient storage means. Yet further, it is an object of the present invention to provide such an assistive device that is not as complex, power-supply dependent or costly as existing automated benders. Thus, it is an object of the invention to convert a conventional hand bender into a modular mechanical conduit bending system.
These and other objects are achieved with the present invention, which is a stand for use with a hand bender of selectable angle type. The assistive bender stand includes a bender securing assembly and a base that provides the foundation and, when necessary, leverage, to bend conduit, pipe, or tube, as desired. The combination of the bender securing assembly and the base, which may optionally be of adjustable dimensions, enables a user to leverage the capability of an inexpensive hand bender into formation of accurate bends. Moreover, the securing assembly and base combination firmly fixes the handle portion of the bender in a stationary position not subject to random movements of the user.
The securing assembly includes a releasable and adjustable bender securing frame and a support frame that is removably couplable to the base. The securing frame may be fixedly or preferably rotatably couplable to the support frame so that the position of the hand bender secured therein may be adjusted as desired and so that a centerline of the conduit may be maintained through a bending. The securing frame includes a handle capturing section that may either be formed in recesses of opposing faces of that section or that may be applied to those opposing faces. The securing frame is preferably formed of material sufficiently rigid to withstand the type of stresses that may be expected in the course of bending conduit, pipe or tubing. One material found to be suitable is steel coated with an oxidation prevention material; however, those skilled in the art that the device may be formed of a material other than steel.
The base of the stand includes an attachment section for connecting to the securing assembly. It also includes a primary frame that is designed to be set in place on a substrate and forms the structural foundation for the assistive bender stand of the present invention. Additionally, a slidable frame extension assembly may be slidably secured to the primary frame to provide supplemental leverage support in the event a particular conduit is long or of greater-than-average rigidity.
The base assembly may further include a conduit support bar that is detachably connected to the primary frame. The conduit support bar is coupled to a bar frame so that the height of the support bar with respect to the primary frame may be of adjustable height. The support bar is preferably formed of a material, or at least coated with a material, that allows for smooth passage of a conduit to be shaped. A variety of low-friction materials or coatings may be suitable for that purpose including, but not limited to, polyethylene tubing.
The support bar provides a height dimension to the overall structure of the device of the present invention that enables the formation of multiple bends in a single conduit run. Specifically, prior hand bending required placement of the conduit on a surface, such as a floor, to provide the user with the leverage necessary to create the bend of selected height. However, in that situation, after the first shaping of the conduit, it is not possible to make a second opposing bend, for example. The adjustable height of the support bar provides the height differential necessary to create multiple bends in a single conduit run while maintaining the necessary leverage to form those bends. Further, the support bar compensates for radius changes associated with the various hand benders available including, but not limited to, the {fraction (1/2)}xe2x80x3, {fraction (3/4)}xe2x80x3, 1xe2x80x3, and 1xc2xcxe2x80x3 hand benders, which benders are fixed at radii of 5xe2x80x3, 6xe2x80x3, and 7xe2x80x3, respectively. Through use of the support bar, the conduit is maintained level throughout the bending process and in order to maintain a 90xc2x0 bend when desired.
The combination of the securing frame and the support frame of the present invention provide a convenient stand that allows a user to greatly increase the capabilities of a relatively inexpensive hand bender. In particular, the user need only obtain the stand of the present invention and one or more hand benders of selectable head angles to create a mechanical hand bending system that is portable and therefore usable for a variety of applications. In addition, combining the present stand device with a hand bender and a conduit level such as The Eliminator(trademark) offered by Bending Technologies, Inc. of Fairfield, Me., ensures easy and accurate bend formation. This is achieved without the expense, complexity, and other noted limitations associated with an automated bender. Further, the assistive bender stand of the present invention is easily portable by a single individual and may be conveniently stowed in a secure location on site.
These and other advantages of the present invention will become apparent upon review of the following description and the accompanying drawing.